This only happens when you are using react-native@0.48.3, and your XCode is in version 9.0

* Update the comment for tabsStyle in Android

* for -> on

* Update top-level-api.md

Fixes #1844

This commit adds support for fade and slide-horizontal animations for modals and a few other animation related changes:

* Support defining animationType when calling dismissModal
* Support fade and slide horizontal animations for modals
* Slightly reworked current screen animations timings
* Fixed slide-horizontal x offset and removed alpha

This is a breaking change and has to be opt-in. To prevent host.clear from being called,
Override `clearHostOnActivityDestroy` in MainApplication and return false:

```java
    @Override
    public boolean clearHostOnActivityDestroy() {
        return false;
    }
```

If host isn't cleared, the next time the app is opened react context might still be initialized.
In this case we emit appLaunched event which has to be handled in Js:

```js
  Promise.resolve(Navigation.isAppLaunched())
      .then((appLaunched) => {
        if (appLaunched) {
          startApp();
        }
        new NativeEventsReceiver().appLaunched(() => {
          startApp();
        });
      })
```

This converts from using a deprecated attribute.

* add disabledButtonColor in order to set navigation button disabled color

* add disabledButtonColor to the docs

Fixes #1007

* Add font family support on bottom tabs

* import missing classes

* import missing class

* update document

* Support customize icon for left nav button in android

* Add navBar navBarTextFontSize support for android

* Add missing parameter instruction for in app notification

* Merge changes as origin master

Ability to set a flat border under the TopBar. `topBarElevationShadowEnabled` should be set to true if using this feature.

* testing

* test

* try fix props on topTabs

* Test xml menu

* Add titleBarHeight

* Remove test

* Add to StyleParams

* Add topTabsHeight

* Fix styleParams type

* Add navBarFontBold

* Add typeface package

* Remove unused debugging

* add adjust soft input optional config for Lightbox on android platform

* Add doc about adjustSoftInput for showLightBox

* Add initialTabIndex support to RCCTabBarController

* Add initialTabIndex support to BottomTabsLayout

closes #1694

fixes #1675

To match the rest of the styling

As the screen api document mentions that it can be done statically, it's best to mention it here as well.